2 results about "Bright star" patented technology

The invention discloses a star point motion parameter estimation method for a high-dynamic star sensor. The method specifically comprises the following steps: (1) acquiring a star map under a dynamic condition through a fixed star sensor; (2) carrying out filtering preprocessing on the fixed star sensor image obtained in the step (1); (3) carrying out threshold segmentation on the image processed in the step (2) and carrying out connected domain extraction to obtain rough star points; (4) selecting the brightest star point in the star points obtained in the step (3); (5) obtaining a sub-pixel star point track by using the brightest star point adjacent area obtained in the step (4) and adopting a Zernike moment sub-pixel edge extraction method; and (6) utilizing the sub-pixel star point trajectory obtained in the step (5), and adopting least square fitting to obtain star point motion parameters. The method has the beneficial effects that the precision of star point trailing length and angle estimation is improved, so that the extraction precision of star points in a dynamic environment is improved, and the precision of a fixed star sensor is improved.

A method for measuring a shape of a reflector surface of a heliostat at night using a bright star at different elevation and azimuthal settings according to an embodiment of the current invention includes setting the heliostat in fixed orientation such that aberrated and overlapping star images formed are translated due to Earth's rotation in a translation direction across the heliostat array receiver; viewing images of the bright star using a fixed array of cameras placed at or near an array receiver of the heliostat, wherein each camera of the fixed array of cameras has a large aperture lens, and simultaneous exposures are made quickly enough and repeated for long enough, so that, as they translate past the cameras, the aberrated star image is fully sampled in two dimensions, and wherein every point on the reflector surface of the heliostat appears in one or more of the recorded images as being bright from reflected starlight; and processing the recorded images from the fixed array of cameras with a data processor to obtain the surface shape by integration of the surface slopes.